Channel Tunnel high-speed train company Eurostar is bidding to operate a key Scotland to London rail route.

Eurostar is launching a joint bid with French company Keolis to run the East Coast line.

The successful bidder for East Coast, which has been operated in the public sector since 2009, is expected to be announced in October 2014, with the new franchise starting in February 2015.

Eurostar would take a minority share in the Keolis-Eurostar consortium.

Eurostar chief executive Nicolas Petrovic said: "By joining forces with Keolis, we bring a unique blend of expertise and innovation with a fresh perspective.

"The East Coast franchise is a vital economic artery and a key route for both business and leisure passengers which represents an exciting opportunity for future growth and investment."

East Coast has been run under the control of the Department for Transport since November 2009 after National Express pulled out.

Its return to the private sector has been opposed by Labour and rail unions who have pointed out that the company offers good value for money for taxpayers.

Keolis, which is majority owned by French rail company SNCF, has considerable experience in UK rail. It jointly operates four franchises - Southern, Southeastern, London Midland and TransPennine Express. Keolis also operates the NET network.

Keolis UK chief executive Alistair Gordon said: "I believe that our ability to draw upon an international track record of delivering complex long-distance services, coupled with Eurostar's reputation for customer excellence, is a unique proposition."

However Mick Whelan, general secretary of train drivers' union Aslef, said: "National Express, when it handed back the keys, left the East Coast route in chaos. It has been run with spectacular success in the public sector ever since.

'The East Coast line delivers a better deal to the public purse - to each and every taxpayer in Britain - than any other railway line. It is a key tool against which we can measure the success or failure of the privatised train operating companies.

'It's shameful that a Government that fears it will lose the next election is tripping over itself in its rush to re-privatise a successful public service. Passengers, staff, and the taxpayer are all set to lose out."